Time & Date

Convert clock times between 12-hour AM/PM and 24-hour formats, single or in bulk.

Add or subtract a number of business days to a date, skipping weekends and custom holidays.

Add or subtract days, weeks, months, or years from a date and get the resulting date in multiple formats.

Calculate exact age from a birth date in years, months, days, plus total days, hours, and the next birthday countdown.

Convert an age or elapsed time on Earth to equivalent years on other planets.

Convert a pasted list of Unix timestamps to human dates (or dates back to timestamps) in bulk.

Find dates of life milestones: 10,000 days old, 1 billion seconds, next round-number birthday.

Count working days between two dates, excluding weekends, or add a number of business days to a start date.

Find the Chinese zodiac animal, element, and yin/yang for any year (approximate by year).

Compute the duration between two times of day, optionally wrapping past midnight.

Compute the exact remaining time from now to a target datetime, broken into units.

Build a standard cron expression from dropdowns for minute, hour, day, month, and weekday with a human-readable preview.

Explain a cron expression in plain English and preview the next run times.

Expand each field of a cron expression into the explicit set of matching values.

List the next N execution datetimes for a 5-field cron expression from a chosen start time.

Calculate the duration between two dates in years, days, hours and more.

Parse any date string and reformat it into common patterns (ISO 8601, RFC 2822, US, EU, locale strings) all at once.

Searchable cheatsheet of date-format tokens across moment, date-fns, strftime, Java, and Unicode LDML.

Split a date range into equal chunks or fixed-length intervals (e.g. weekly buckets).

Cheatsheet of the same instant rendered in RFC 3339, RFC 2822, ISO 8601, HTTP-date, SQL, and more.

Find the ordinal day-of-year for any date, days remaining in the year, and convert an ordinal day back to a date.

Show how much of a day, week, month, year, hour, or minute has elapsed for a given moment.

Measure the span between two datetimes simultaneously in years, months, weeks, days, hours, minutes, and seconds.

Count the exact days, weeks, hours, and minutes between today and a target future or past date.

Convert standard clock time to French Revolutionary decimal time (10 hours/day) and back.

Turn a raw number of seconds or milliseconds into a human phrase like '2 days, 3 hours, 5 minutes'.

Parse human duration text like '1h30m', '2 days 4 hours', or '90s' into total seconds and milliseconds.

Convert a Unix timestamp between seconds, milliseconds, microseconds, and nanoseconds with auto-detection.

Convert a datetime across fixed UTC offsets (e.g. +05:30 to -08:00) without DST guessing.

See one meeting time across multiple fixed UTC offsets to find an overlap.

Parse ISO 8601 duration strings like P1Y2M10DT2H30M into total seconds and a human-readable breakdown.

Break down an ISO 8601 date-time string into its components (year, month, day, hour, offset, week) and validate it.

Convert between a calendar date and its ISO-8601 week-date form (YYYY-Www-D).

Find the ISO 8601 week number for any date (and day-of-year).

Convert Gregorian dates to astronomical Julian Day Number / Julian Date and back.

Check if any year is a leap year and list nearby leap years with the rule explained.

Estimates the dollar cost of a meeting from attendee count, hourly rates, and duration.

Estimate the moon phase, illumination percentage, and lunar age for any date algorithmically.

Find the next (or Nth) date that falls on a chosen weekday from a starting date.

Find dates like 'the 3rd Thursday of November' or 'the last Monday of May'.

Convert between calendar dates and ordinal dates (year + day-of-year, YYYY-DDD).

Determine the calendar or fiscal quarter, half, and period dates for any date.

Generate the next N dates for a simple recurrence (daily, weekly, monthly, yearly with interval).

Turn a timestamp or date into human-friendly relative phrasing like '3 hours ago' or 'in 2 days' across locales.

Converts between SMPTE timecode (HH:MM:SS:FF) and total frame counts at a chosen frame rate.

Convert Gregorian dates to TNG-era stardates and back using the common fan formula.

Apply a C/Python strftime format string to a chosen datetime and see the rendered output live.

Convert any time to Swatch Internet Time beats (BMT, @000-@999) and back.

Adds and subtracts a list of HH:MM:SS durations and shows the running and total result.

Show key time-storage overflow dates (Year 2038, 2-digit Y2K, 32-bit, 64-bit limits).

Convert a value between nanoseconds, microseconds, milliseconds, seconds, minutes, hours, and days.

Classify a time into parts of day (morning, afternoon, evening, night) and solar/clock segments.

Convert a date/time across timezones using the browser’s IANA database.

Render a datetime using an Intl.DateTimeFormat-style or LDML pattern and preview the result.

Convert nanosecond-precision Unix timestamps to date-time and back without floating-point loss.

Convert between Unix timestamps and human-readable dates (local & UTC).

Live ticking display of the current Unix timestamp in seconds, milliseconds, and microseconds, with a one-click copy and pause toggle.

Convert an ISO week number and year into the start and end dates of that week, and vice versa.

Determine which week of the month a date falls in, using several common counting conventions.

Find which day of the week any date falls on, with a Doomsday-rule mental-math walkthrough.

Count full weeks, months, and weekends remaining until a future date.

Find the tropical (Western) zodiac sign and its date range for any birth date.

Compute net working hours between two datetimes, excluding nights, weekends, and lunch.